I regret to inform everyone that my Molotov cocktail escaped my sandbox last night and somehow made its way into a CEO’s house. It has since been found burning in a place it absolutely did not belong, and I’m currently investigating how this happened, which will involve carefully inspecting the fire and roasting some marshmallows until the truth becomes clear. Thank you for your cooperation during this trying time.
TheEighthDoctor
I went back to the book and it says "It had long been the custom amongst the dragonlords of Valyria to wed brother to sister, to keep the bloodlines pure".
This is in the context of Aegon the Conqueror, so, yes it was already a practice before the Doom.
Nothing says luxury car like trashy ads on your dash
That's true, the incenst is only necessary to keep the dragon riding blood in the family, if most of the noble houses have dragon riding blood then it doesn't matter.
There is also the problem of the stillborn babies with dragon wings and scales.
Targaryens also were around for at least the same time, maybe more, because they were already considered an old house when Daenys foresaw the doom, and that was like 500 years before the game of thrones story
Would be lore accurate with how atrocious I always was at getting hints
What if she has the tiniest of skirts, that's when I'm fucked
Apply the sacred unguents and start the maintenance rites

Hollandaya Sauce